Corona-discharge air mover and purifier for fireplace and hearth

ABSTRACT

A fireplace for warming an environment is provided. The fireplace comprise a combustion chamber, a passage, and at least one corona discharge apparatus. The passage is adjacent to the combustion chamber and extends between an inlet and an outlet. The at least one corona discharge apparatus is position within the passage to draw a fluid into the passage through the inlet and to expel the fluid through the outlet.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This patent application claims the benefit of U.S. Provisional PatentApplication No. 60/632,226, filed Nov. 30, 2004, the teachings anddisclosure of which are hereby incorporated in their entireties byreference thereto.

FIELD OF THE INVENTION

This invention pertains to fireplace and hearth heating systems, andmore particularly to blowers for use in fireplace and hearth heatingsystems.

BACKGROUND OF THE INVENTION

Fireplaces typically employ conventional rotating air movers such asfans and blowers to draw return air into a duct or plenum, force itthrough a heat exchanger, and then expel heated air back out into theroom. An air filter may be added to further condition the air.

Unfortunately, fans and blowers tend to be noisy, especially in therelative quiet of a living room or bedroom. Furthermore, fans andblowers contain rotating and moving parts that usually wear out overtime. Conventional air filters need to be replaced periodically, whichincreases the cost of ownership of such a system.

Therefore, an apparatus that can quietly move, and perhaps even filter,the air that is heated by a fireplace without rotating parts would bedesirable. The invention provides such an apparatus. These and otheradvantages of the invention, as well as additional inventive features,will be apparent from the description of the invention provided herein.

BRIEF SUMMARY OF THE INVENTION

In view of the above, the present invention provides a new and improvedair mover and purifier for a fireplace and hearth that overcomes one ormore problems existing in the art. More particularly, the presentinvention provides a new and improved air mover and purifier forresidential fireplace and hearth heating systems having a forced airduct or plenum.

In one embodiment of the present invention, the invention replaces a fanor blower with a corona-discharge air-moving apparatus that contains nomoving parts. The invention is quieter, more efficient and more reliablethan fans or blowers and provides air purification without the use ofexternal filters or devices.

In one aspect, the invention provides a fireplace. The fireplacecomprises a combustion chamber, a passage, and at least one coronadischarge apparatus. The passage is adjacent to the combustion chamberand extends between an inlet and an outlet. The at least one coronadischarge apparatus is positioned within the passage to draw a fluidinto the passage through the inlet and to expel the fluid through theoutlet.

In another aspect, the invention provides a corona-discharge air moverand purifier apparatus for a fireplace having a combustion chamberconfigured to receive a fuel. The fuel generates heat within thecombustion chamber when combusted. A passage adjacent to the combustionchamber extends between an inlet and an outlet. The corona-discharge airmover and purifier apparatus comprises a first positively chargedemitter array adapted to be positioned in the passage and a firstnegatively charged collector array adapted to be positioned in thepassage in spaced relation to the first positively charged emitterarray. The first positively charged emitter array and the first negativecharged collector array are operative to cooperatively produce anelectric wind in the passage. As such, air is drawn from the environmentinto the passage through the inlet, heated from the combustion chamber,and expelled through the outlet into the environment to warm theenvironment during combustion of the fuel in the combustion chamber.

In yet another aspect, the invention provides method of heating anenvironment using a fireplace having a combustion chamber configured toreceive a fuel. The fuel generates heat within the combustion chamberwhen combusted. A passage is adjacent to the combustion chamber andextends between an inlet and an outlet. The method comprises the step ofinstalling a corona discharge apparatus in the passage. The installedcorona discharge apparatus is then energized to produce an electric windin the passage. The electric wind results in air being drawn from theenvironment into the passage through the inlet, heated from thecombustion chamber, and expelled through the outlet into the environmentto warm the environment during combustion of the fuel in the combustionchamber.

Other aspects, objectives and advantages of the invention will becomemore apparent from the following detailed description when taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated in and forming a part of thespecification illustrate several aspects of the present invention and,together with the description, serve to explain the principles of theinvention. In the drawings:

FIG. 1 is a simplified side view of an exemplary embodiment of afireplace including an air moving apparatus constructed in accordancewith the teachings of the present invention.

While the invention will be described in connection with certainpreferred embodiments, there is no intent to limit it to thoseembodiments. On the contrary, the intent is to cover all alternatives,modifications and equivalents as included within the spirit and scope ofthe invention as defined by the appended claims.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, a hearth or fireplace 10 constructed in accordancewith the teachings of the present invention, which may be installed,e.g., in a residential dwelling or commercial building, is illustrated.As will be described more fully below, the fireplace 10 of the presentinvention is constructed to quietly move a fluid (e.g., air) through thefireplace without the need for moving or rotating parts.

As shown, the fireplace 10 may sit on a base 12 and comprises a body 14and a flue 16. The base 12 is preferably constructed of a heat and fireresistant material such as stone, brick, concrete, and the like. Such abase 12 for the fireplace 10 typically rests on and above the foundationof the structure and generally supports the body 14. The flue 16, whichsits atop the body 14, is configured to transport hot gases to thechimney (not shown) and out of the structure.

The body 14 includes a combustion chamber 18, a passage 20, and one ormore corona discharge apparatuses 22. The body 14 of the fireplace 10defines a front face 24 that conventionally faces toward an environmentsuch as a living room, bedroom, and the like. Since the fireplace 10 canbe installed in a flush or recessed orientation, the front face 24 ofthe body 14 can be planar or offset from a wall 26.

The combustion chamber 18 has an open front 28 that is generally exposedto the environment. This open front 28 may be closed off by glass doorsor the like in highly efficient embodiments. In such embodiments, thecombustion chamber 18 is often fed with outside air to support thecombustion. In addition, the combustion chamber 18 defines a back wall30, a floor 32, and a roof 34. The combustion chamber 18 is sized,dimensioned, and otherwise configured to receive a fuel 36 such as, forexample, wood, natural gas, pellets, and the like. When the fuel 36 iscombusted, heat is generated within the combustion chamber 18.

The roof 34 of the combustion chamber 18 includes an aperture 38 thatcouples the combustion chamber 18 and the flue 16. Therefore, when adamper 40 in the flue 16 is opened, the smoke and other combustionbyproducts produced by the combusted fuel 36 is able to rise and passupwardly through the flue 16. To promote the ascension of the smoke andother combustion byproducts, one or more of the roof 34 and flue 16 caninclude a portion that is upwardly canted or contoured.

The passage 20 in the body 14 extends between an inlet 42 and an outlet44. The inlet 42 and outlet 44 each open through the front face 24 ofthe body 14 as shown in FIG. 1. In the illustrated embodiment, theoutlet 44 is disposed vertically above the inlet 42. This allows thepassage 20 to take in cooler air near the floor of the dwelling toincrease the occupants' comfort. Each of the inlet and outlet 42, 44 canbe protected by a cover 46, a grate, and the like. As FIG. 1 depicts, inone embodiment all or at least a portion of the passage 20 is proximateand/or adjacent to the combustion chamber 18 to increase the ability ofthe heat in the combustion chamber 18 to heat the air in the passage 20.Preferably, the passage 20 runs along a substantial portion of thecombustion chamber 18.

In the illustrated embodiment of FIG. 1, the passage 20 begins at theinlet 42, passes beneath the floor 34, skirts the back wall 30, runsalong the roof 32, and then terminates at the outlet 44. As such, theheat generated by the combusted fuel 36 in the combustion chamber 18 canbe conductively and/or convectively transferred to the air movingthrough or residing in the passage 20.

Each of the corona discharge apparatuses 22 in the passage 20 is anelectrical device that relies on corona discharge and ion chargeattraction to move air and, preferably, filter particles and pollutantsfrom the air. In the illustrated embodiment, three of the coronadischarge apparatuses 22 are shown in the passage 20 although more orfewer may be used.

A typical corona discharge apparatus 22 employs numerous coronadischarge electrodes 48 arranged in arrays and spaced apart fromnumerous negatively charged attracting electrodes 50 that are alsoarranged in arrays. When assembled into an array, the corona dischargeelectrodes 48 can be referred to as an emitter array. Likewise, theattracting electrodes 50 can be referred to a collector array. Due tothe many array configurations and electrode shapes that can be used, thearrays of the corona discharge electrodes 48 and the attractingelectrodes 50 have been shown in FIG. 1 in a simplified form.

Each of the corona discharge electrodes 48 and attracting electrodes 50is coupled to and charged by a high-voltage power supply 51. Theelectrodes 48 and 50 are also preferably controlled and/or managed byrelated control electronics (not shown). In addition, the coronadischarge electrodes 48 are typically asymmetrical with respect to theattracting electrodes 50. In one embodiment, the corona dischargeelectrodes 48 are highly curved and resemble the tip of a needle or anarrow wire while the attracting electrodes 50 take the form of a flatplate or a ground plane. The curvature of the corona dischargeelectrodes 48 ensures a high potential gradient around that electrode.

The high potential gradient generated at or near the corona dischargeelectrodes 48 basically pulls apart the neutral air molecules in theimmediate area. What remains after each neutral air molecule has beendismantled is a positively charged ion and a negatively chargedelectron. Due to the strong electric field near the corona dischargeelectrode 48, the ion and electron are increasingly separated from eachother, prevented from recombining, and accelerated. Therefore, the ionand electron are both imparted with kinetic energy. Moreover, since aportion of the air molecules in the passage 20 is ionized, the air inthe passage becomes a conducting medium, the circuit including thecorona discharge electrodes 48 and the attracting electrodes 50 iscompleted, and a current flow can be sustained.

The negatively charged electrons are persuaded to move toward thepositively charged corona discharge electrodes 48 due to the differencein charge between them. When the rapidly moving and acceleratingelectrons collide with other neutral air molecules in the area, furtherpositive ion/electron pairs are created. As more and more positive/ionelectric pairs are produced, an electron avalanche is established. Theelectron avalanche sustains and/or perpetuates the corona dischargeprocess.

In contrast to the negatively charged electrons, the positively chargedions are persuaded to move from near the corona discharge electrodes 48toward the attracting electrodes 50. This movement is due to thedifference in charge between the positively charged ions and thenegatively charged attracting electrodes. Like the electrons, when thepositively charged ions move they also collide with neutral airmolecules. When they collide, the positively charged ions can transfersome of their momentum as well as excess charge to the neutral airmolecules. Therefore, the neutral air molecules are knocked toward theattracting electrode 50 or are ionized and then drawn to the attractingelectrode 50. In either case, the positively charged ions and other airmolecules end up flowing from the corona discharge electrodes 48 towardthe attracting electrodes 50.

The movement or flow of the air particles away from the corona dischargeelectrodes 48 and toward the attracting electrodes 50 causes or resultsin what is referred to by those skilled in the art as an electric windor electrostatic fluid acceleration. In the illustrated embodiment ofFIG. 1, the electric wind travels through the passage 20 in a directiondepicted by arrows 52.

In one embodiment, the velocity and volume of the air moving through thepassage 20 is proportional to the voltage difference between theelectrodes 48, 50 and the size of the arrays. By varying the potentialbetween the electrodes 48, 50, the size and dimensions of the passage,and the like, the velocity and volume of the electric wind can beincreased and decreased over a continuous range as desired. In anyparticular configuration, this range may be manually adjusted with asimple adjustment knob 49 or remote control that varies the electricpotential between the electrodes 48, 50. With the appropriateconfiguration, air flows exceeding six hundred cubic feet per minute arepossible.

When the positively charged ions creating the electric wind reach theattracting electrodes 50, the positive charge is removed by permitting arecombination of the negatively charged electrons with the positivelycharged ions. Due to the recombination, neutral air molecules once againexists in the passage 20. Advantageously, these neutral air moleculesretain their velocity and direction.

In a preferred embodiment, one or more corona discharge apparatuses 22can be disposed within either or both of the passage 20 and the flue 16for the purpose of cleaning and scrubbing the air. Such beneficial anddesirable filtering can be performed in addition to generating theelectric wind. As known to those skilled in the art, contaminants andparticles tend to adhere to the attracting electrode 50 during thecorona discharge process. Therefore, both the air passing through thepassage 20 and the exhaust gases exiting the combustion chamber 18 andbeing expelled from the structure can be purified. Notably, theattracting electrodes 50, which are often plates, are preferablyremovable to permit inspection, cleaning, and replacement. In analternative embodiment, the entire corona discharge apparatuses 22 areremovable. Moreover, besides providing air movement and air cleaning,the corona discharge apparatuses 22 may also control flue airflow in anoscillatory manner to achieve unique combustion effects.

As is known in the art, several patents and published applications haverecognized that corona discharge devices may be used to generate ionsand accelerate and filter fluids such as air. Such patents and publishedapplications that describe fluid and/or air moving devices andtechnology include the following U.S. Pat. Nos. 3,638,058, 3,699,387,3,751,715, 4,210,847, 4,231,766, 4,380,720, 4,643,745, 4,789,801,5,077,500, 5,667,564, 6,176,977, 6,504,308, 6,664,741, and 6,727,657 andU.S. Pub. Pat. Applns. 2004/40217720, 2004/0212329, 2004/0183454,2004/0155612, 2004/0004797, 2004/0004440, 2003/0234618, and2003/0090209. The teachings and disclosure of each of these patents andpublished applications are incorporated in their entireties by referencethereto.

While other ion discharge or corona fluid movement technologies may beemployed in the system and method of the present invention, a preferredembodiment of the present invention utilizes the technology described inone or more of the preceding patents and/or published applications, andmost preferably, the technology described in U.S. Pat. Nos. 6,504,308,6,664,741, and 6,727,657 issued to Kronos Advanced Technologies, Inc.,of Belmont, Mass. The teachings and disclosure of each of these patentsare also incorporated in their entireties by reference thereto.

In a preferred embodiment, the fireplace 10 further comprises an ozonedepletion apparatus 53 for reducing the amount of ozone in the fluid. Ingeneral, the ozone depletion apparatus 53 is any system, device, ormethod having the ability to degenerate ozone into oxygen (i.e.,dioxide) and/or absorb ozone. In particular, the ozone depletionapparatus 53 can be a filter, a catalyst composition situated proximatethe fluid, and the like. When the fireplace 10 is equipped with theozone depletion apparatus 53, the ozone generated by the coronadischarge apparatuses 22 can be maintained below a desired level,relegated to within a predetermined range, and otherwise managed.

While the ozone depletion apparatus 53 can be situated in a variety ofdifferent locations relative to the one or more corona dischargeapparatuses 22, the ozone depletion apparatus is preferably disposedwithin the passage 20 proximate the outlet 44. In an exemplaryembodiment, the ozone depletion apparatus 53 is generally downstream ofthe last corona discharge apparatus 22 in the fireplace 10. As such, airflowing out of the outlet 44 is purified by the ozone depletionapparatus 53 prior to entering the environment.

As is known in the art, several patents have recognized that ozonedepletion devices and systems may be used to convert ozone to oxygen,absorb ozone, and the like. Such patents that describe converting andabsorbing devices, methods, and technology include the following U.S.Pat. Nos. 4,343,776, 4,405,507, 5,422,331, 6,375,902, 6,375,905, and6,699,529. The teachings and disclosure of each of these patents areincorporated in their entireties by reference thereto.

In operation, air is drawn into the passage 20 of the fireplace 10through the inlet 42 due to the activation of one or more of the coronadischarge apparatuses 22 and the corona discharge process as discussedabove. Once drawn inside the passage 20, the air (or particles thereof)continues to move through the passage 20 in the direction indicated bythe arrows 52. While residing within the passage 20, the heat from thefuel 36 being combusted in the combustion chamber 18 is conductivelyand/or convectively transferred to the air.

After the air flowing through the passage 20 has been heated, the air isexpelled and/or exhausted into the environment through the outlet 44 bythe corona discharge process. Since the air has been heated by thecombustion of the fuel 36 in the combustion chamber 18, an ambienttemperature of the environment is elevated. In other words, theenvironment is warmed by the air that has circulated through thefireplace 10 and been heated.

In a preferred embodiment, at least one of the corona dischargeapparatuses 22 illustrated in FIG. 1 also filters and cleans the airtraveling through the passage 20 of the fireplace 10. In a furtherpreferred embodiment, at least one of the corona discharge apparatuses22 filters and scrubs the exhaust gases leaving the combustion chamber18.

Advantageously, the present invention provides quieter hearth orfireplace 10 operation compared to when a mechanical fan or a blower isemployed. The present invention also allows for a smaller, more flexiblefootprint than a large, circular shaped fan or blower will allow. Thisenables a larger combustion chamber 18 in the same overall volume forthe hearth or fireplace 10. Moreover, the air can be purified by thecorona discharge apparatuses 22 and the velocity of the air can bevariably controlled.

All references, including publications, patent applications, and patentscited herein are hereby incorporated by reference to the same extent asif each reference were individually and specifically indicated to beincorporated by reference and were set forth in its entirety herein.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) is to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. Recitation of ranges of valuesherein are merely intended to serve as a shorthand method of referringindividually to each separate value falling within the range, unlessotherwise indicated herein, and each separate value is incorporated intothe specification as if it were individually recited herein. All methodsdescribed herein can be performed in any suitable order unless otherwiseindicated herein or otherwise clearly contradicted by context. The useof any and all examples, or exemplary language (e.g., “such as”)provided herein, is intended merely to better illuminate the inventionand does not pose a limitation on the scope of the invention unlessotherwise claimed. No language in the specification should be construedas indicating any non-claimed element as essential to the practice ofthe invention.

Preferred embodiments of this invention are described herein, includingthe best mode known to the inventors for carrying out the invention.Variations of those preferred embodiments may become apparent to thoseof ordinary skill in the art upon reading the foregoing description. Theinventors expect skilled artisans to employ such variations asappropriate, and the inventors intend for the invention to be practicedotherwise than as specifically described herein. Accordingly, thisinvention includes all modifications and equivalents of the subjectmatter recited in the claims appended hereto as permitted by applicablelaw. Moreover, any combination of the above-described elements in allpossible variations thereof is encompassed by the invention unlessotherwise indicated herein or otherwise clearly contradicted by context.

1. A fireplace comprising: a combustion chamber; a passage adjacent to the combustion chamber, the passage extending between an inlet and an outlet; and at least one corona discharge apparatus positioned within the passage to draw a fluid into the passage through the inlet and to expel the fluid through the outlet.
 2. The fireplace of claim 1, wherein the inlet is positioned below the combustion chamber so as to allow cooler fluid to be drawn into the passage, and wherein the outlet is positioned above the combustion chamber to allow to fluid in the passage to be heated when fuel is combusted in the combustion chamber.
 3. The fireplace of claim 1, further comprising means operatively coupled to the at least one corona discharge apparatus for varying a flow rate of the fluid through the passage.
 4. The fireplace of claim 1, wherein the inlet and the outlet are formed in a front face of the fireplace and the outlet is disposed vertically above the inlet.
 5. The fireplace of claim 1, wherein the fireplace further comprises an ozone depletion apparatus for removing ozone from the fluid.
 6. The fireplace of claim 1, wherein the passage is oriented relative to the combustion chamber to heat the fluid within the passage.
 7. The fireplace of claim 1, further comprising a flue coupled to a roof of the combustion chamber, the flue including at least one corona discharge apparatus positioned therein for filtering smoke and other combustion byproducts during combustion within the combustion chamber.
 8. The fireplace of claim 7, wherein at least one electrode in the at least one corona discharge apparatus is removable from the flue for inspection, cleaning, and replacement.
 9. The fireplace of claim 7, wherein the at least one corona discharge apparatus positioned within the flue permits a variable flow of air to flow through the flue to control the combustion in the combustion chamber.
 10. The fireplace of claim 1, wherein the at least one corona discharge apparatus comprises a positively charged emitter array in spaced relation to a negatively charged collector array.
 11. The fireplace of claim 1, wherein the at least one corona discharge apparatus moves the fluid through the passage at about six hundred cubic feet per minute when energized.
 12. The fireplace of claim 1, wherein at least one of the at least one corona discharge apparatuses is removably positioned in the passage to allow cleaning thereof.
 13. The fireplace of claim 1, wherein the fireplace further includes a high voltage power supply operatively coupled to the at least one corona discharge apparatus.
 14. A corona-discharge air mover and purifier apparatus for a fireplace having a combustion chamber configured to receive a fuel, the fuel generating heat within the combustion chamber when combusted, and a passage adjacent to the combustion chamber, the passage extending between an inlet and an outlet, comprising: a first positively charged emitter array adapted to be positioned in the passage; and a first negatively charged collector array adapted to be positioned in the passage in spaced relation to the first positively charged emitter array, the first positively charged emitter array and the first negative charged collector array being operative to cooperatively produce an electric wind in the passage such that air is drawn from the environment into the passage through the inlet, heated from the combustion chamber, and expelled through the outlet into the environment to warm the environment during combustion of the fuel in the combustion chamber.
 15. The apparatus of claim 14, further comprising a second positively charged emitter array adapted to be positioned in the passage and a second negatively charged collector array adapted to be positioned in the passage in spaced relation to one another such that they cooperatively aid the electric wind in the passage.
 16. The apparatus of claim 14, wherein the first positively charged emitter array and the first negative charged collector array operative to cooperatively filter the air drawn from the environment and flowing in the passage.
 17. The apparatus of claim 14, further comprising a second positively charged emitter array adapted to be positioned in a flue of the fireplace and a second negatively charged collector array adapted to be positioned in the flue in spaced relation to the second positively charged emitter array, the second positively charged emitter array and the second negative charged collector array being operative to cooperatively produce an electric wind in the flue to aid combustion in the combustion chamber.
 18. A method of heating an environment using a fireplace having a combustion chamber configured to receive a fuel, the fuel generating heat within the combustion chamber when combusted, and a passage adjacent to the combustion chamber, the passage extending between an inlet and an outlet, the method comprising the steps of: installing a corona discharge apparatus in the passage; energizing the corona discharge apparatus to produce an electric wind in the passage such that air is drawn from the environment into the passage through the inlet, heated from the combustion chamber, and expelled through the outlet into the environment to warm the environment during combustion of the fuel in the combustion chamber.
 19. The method of claim 18, wherein the step of installing the corona discharge apparatus comprises the steps of: installing a first positively charged emitter array in the passage; installing a first negatively charged collector array in the passage in spaced relation to the first positively charged emitter array.
 20. The method of claim 19, wherein the step of installing the corona discharge apparatus further comprises the steps of: installing a second positively charged emitter array in the passage; installing a second negatively charged collector array in the passage in spaced relation to the second positively charged emitter array. 